What is the Internet and How Does it Work

What is the Internet?

The internet is a global network of computers that can communicate with each other. Think of it like a massive postal system — except instead of letters, it delivers data (web pages, videos, messages) almost instantly.

Every device on the internet — your phone, laptop, or a server in a data centre — has a unique address called an IP address (Internet Protocol address). It looks something like 192.168.1.1 or, in the newer format, 2001:0db8:85a3::8a2e:0370:7334.

How Does a Website Get to Your Screen?

When you type google.com into your browser, here is what happens in less than a second:

Step 1 — DNS Lookup

Your browser doesn't understand "google.com" — it only understands IP addresses. So it asks a DNS server (Domain Name System) to translate "google.com" into an IP address like 142.250.190.46.

Think of DNS as the internet's phone book.

Step 2 — TCP Connection

Your browser opens a connection to Google's server using a protocol called TCP (Transmission Control Protocol). This is like picking up the phone before you can talk.

Step 3 — HTTP Request

Your browser sends an HTTP request — a formal message that says: "Please give me the files for google.com."

GET / HTTP/1.1
Host: google.com

Step 4 — Server Response

Google's server responds with an HTTP response — it sends back the files your browser needs: HTML, CSS, JavaScript, and images.

HTTP/1.1 200 OK
Content-Type: text/html

Step 5 — Browser Renders the Page

Your browser reads the files and draws the page on your screen. That's what you see.

What is HTTP vs HTTPS?

• HTTP (HyperText Transfer Protocol) is the language browsers and servers use to talk to each other.
• HTTPS adds an S for Secure — the connection is encrypted, so nobody can intercept what you send or receive. Always look for HTTPS when entering passwords or payment details.

What is a Server?

A server is just a computer that stores files and serves them to anyone who asks. When you visit a website, you're downloading files from someone else's computer (the server) to your own.

Large companies like Google have thousands of servers in data centres around the world. When you access google.com in Lagos, your request probably goes to a server in Europe or South Africa.

Why Does This Matter for Frontend Engineers?

As a frontend developer, you build the files that servers send to browsers — the HTML, CSS, and JavaScript. Understanding how they travel helps you:

• Diagnose slow pages — maybe too many files are being requested
• Debug network errors — the Network tab in DevTools shows every request
• Understand caching — browsers save files locally so they don't re-download them every time
• Write secure code — knowing about HTTPS and requests helps you avoid security mistakes